Scientia Agricultura Sinica ›› 2024, Vol. 57 ›› Issue (10): 2035-2045.doi: 10.3864/j.issn.0578-1752.2024.10.014

• ANIMAL SCIENCE·VETERINARY SCIENCE • Previous Articles     Next Articles

Prediction Equations of Chicken Metabolizable Energy Values for Grain Ingredients Based on in Vitro Simulated Enzymatic Hydrolysate Gross Energy Values and Chemical Composition

LI Kai(), BAI GuoSong, TENG ChunRan, MA Teng(), ZHONG RuQing, CHEN Liang, ZHANG HongFu   

  1. State Key Laboratory of Animal Nutrition and Feeding/Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing 100193
  • Received:2023-11-18 Accepted:2024-01-11 Online:2024-05-16 Published:2024-05-23
  • Contact: MA Teng

Abstract:

【Objective】 This study aimed to measure the enzymatic hydrolysate gross energy (EHGE) of chicken for wheat, paddy, and brown rice ingredients using a monogastric simulated digestion system, and it also aimed to correlate these measurements with the chemical composition of these ingredients. Moreover, the study sought to establish predictive equations for chicken metabolizable energy values based on the EHGE values and the grain ingredients’ chemical compositions. The findings would provide a reference for the rapid prediction of the metabolizable energy value of grain ingredients for chickens. 【Method】 The EHGE values of nine samples from three sources of wheat, paddy, and brown rice ingredients were measured. Five replicates were set for each grain sample, with one digestion tube per replicate. The apparent metabolizable energy values (AME) and true metabolizable energy values (TME) of the same batch of ingredients were also measured by the free feeding method (FF) and the tube-feeding method (TF). A linear regression model was then used to establish predictive equations for AME and TME based on chemical composition and EHGE values. 【Result】 (1) Based on dry matter basis, the EHGE values of wheat, paddy, and brown rice from the three sources were 14.46, 14.63, and 14.80 MJ·kg-1; 12.52, 13.59, 13.40 MJ·kg-1, and 14.74, 15.10, 15.23 MJ·kg-1, respectively. (2) Ash and neutral detergent fiber exhibited a negative correlation with AME (AMEFF and TMEFF) and TME (AMETF and TMETF) measured by both FF and TF methods (P<0.01). EHGE exhibited a significant positive correlation with AMEFF, TMEFF, AMETF, and TMET measured by both methods (P<0.01), with correlation coefficients of 0.801, 0.864, 0.807, and 0.866, respectively. (3) Compared with the metabolizable energy prediction equations established by EHGE, the prediction equations based on chemical composition had higher coefficients of determination (R2) and lower residual standard deviations (RSD). For AMEFF and TMEFF, Ash was the best predictor, with prediction equations: AMEFF = 16.728-0.842 × Ash (R2= 0.809, RSD = 0.826, P = 0.001), and TMEFF = 16.812-0.842 × Ash (R2= 0.816, RSD = 0.806, P = 0.001). On the other hand, for the AMETF and TMETF variables, NDF was identified as the best predictor. The prediction equations for AMETF and TMETF were AMETF=16.106-0.157×NDF (R2=0.907, RSD=0.523, P<0.001), and TMETF=17.654-0.157×NDF (R2=0.903, RSD= 0.534, P<0.001), respectively. 【Conclusion】 The EHGE of wheat and brown rice was higher than that of paddy, and there was a good correlation between the EHGE values of the three grain ingredients and the metabolizable energy values measured by the in vivo method. The prediction model for the AME and TME of grains based on chemical composition was superior to the prediction model based on EHGE.

Key words: chicken, metabolizable energy, enzymatic hydrolysate gross energy, prediction equation, grain

Table 1

Chemical composition of wheat, paddy, and brown rice (dry matter basis, %)"

原料
Ingredient
编号
No.
干物质
DM
粗蛋白质
CP
粗脂肪
EE
粗灰分
Ash
中性洗涤纤维
NDF
酸性洗涤纤维
ADF
总能
GE (MJ·kg-1)
小麦
Wheat
1 89.16 14.91 1.74 2.11 17.26 3.58 18.65
2 88.04 16.07 1.50 1.34 19.30 4.04 18.67
3 88.64 13.91 2.01 2.09 19.40 3.28 18.60
稻谷
Paddy
1 89.53 6.98 2.28 4.64 20.89 13.87 18.01
2 88.57 8.07 1.55 5.11 23.77 14.93 17.71
3 91.00 9.00 2.63 4.71 23.20 13.79 18.10
糙米
Brown rice
1 86.42 8.56 3.05 0.65 2.11 0.28 18.01
2 86.51 8.51 2.16 0.71 0.88 0.40 18.03
3 87.14 9.19 3.31 0.52 2.08 0.45 18.14

Table 2

Enzymatic hydrolysate gross energy for wheat, paddy, and brown rice (dry matter basis, MJ·kg-1)"

原料
Ingredient
小麦Wheat 稻谷Paddy 糙米Brown rice
1 2 3 1 2 3 1 2 3
酶水解物能值EHGE 14.46 14.63 14.80 12.52 13.59 13.40 14.74 15.10 15.23

Table 3

The correlation coefficient between chemical composition, metabolizable energy values and enzymatic hydrolysate gross energy"

项目
Item
粗蛋白质
CP
粗脂肪
EE
粗灰分
Ash
中性
洗涤纤维
NDF
酸性
洗涤纤维
ADF
总能
GE
FF法
表观代谢能
AMEFF
TF法
表观代谢能
AMETF
FF法
真代谢能
TMEFF
TF法
真代谢能
TMETF
酶水
解物能值
EHGE
粗蛋白质CP 1.000
粗脂肪EE 0.516 1.000
粗灰分Ash -0.332 -0.328 1.000
中性洗涤纤维NDF 0.248 -0.625 0.823** 1.000
酸性洗涤纤维ADF -0.367 -0.300 0.987** 0.798** 1.000
总能GE 0.943** -0.330 -0.389 0.161 -0.430 1.000
FF法表观代谢能AMEFF 0.105 0.256 -0.899** -0.856** -0.882** 0.118 1.000
TF法表观代谢能AMETF 0.018 0.543 -0.935** -0.952** -0.921** 0.099 0.898** 1.000
FF法真代谢能TMEFF 0.103 0.265 -0.903** -0.862** -0.886** 0.116 1.000** 0.905** 1.000
TF法真代谢能TMETF 0.024 0.541 -0.937** -0.950** -0.923** 0.105 0.899** 1.000** 0.905** 1.000
酶水解物能值EHGE 0.405 0.198 -0.908** -0.702* -0.923** 0.376 0.801** 0.864** 0.807** 0.866** 1.000

Table 4

Prediction equations of metabolizable energy from chemical composition and enzymatic hydrolysate gross energy"

能值
(MJ·kg-1 DM)
编号
No.
预测模型 Prediction equation R2 RSD P
截距
Intercept
中性洗涤纤维
NDF
酸性洗涤纤维
ADF
粗灰分
Ash
酶水解物能值EHGE
FF法表观代谢能
AMEFF
1 16.916 -0.156 0.732 0.976 0.003
2 16.189 -0.248 0.777 0.891 0.002
3 16.728 -0.842 0.809 0.826 0.001
4 -7.590 1.560 0.641 1.131 0.010
TF法表观代谢能
AMETF
5 16.106 -0.157 0.907 0.523 <0.001
6 15.280 -0.235 0.848 0.666 <0.001
7 15.782 -0.793 0.875 0.605 <0.001
8 -7.932 1.526 0.746 0.861 0.003
FF法真代谢能
TMEFF
9 17.007 -0.156 0.744 0.951 0.003
10 16.274 -0.248 0.785 0.871 0.002
11 16.812 -0.842 0.816 0.806 0.001
12 -7.583 1.566 0.651 1.109 0.009
TF法真代谢能
TMETF
13 17.654 -0.157 0.903 0.534 <0.001
14 16.834 -0.236 0.851 0.661 <0.001
15 17.338 -0.796 0.878 0.598 <0.001
16 -6.474 1.533 0.750 0.856 0.003

Fig. 1

Prediction equations of apparent metabolizable energy based on chemical composition and enzymatic hydrolysate gross energy W, P, and R represent the wheat, paddy, and brown rice, respectively"

Fig. 2

Prediction equations of true metabolizable energy based on chemical composition and enzymatic hydrolysate gross energy W, P, and R represent the wheat, paddy, and brown rice, respectively"

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